Portsmouth Tap Water Quality Report
Portsmouth's water has 2 contaminants above EPA MCLGs. Consider using a certified water filter for additional protection.
Water system
PORTSMOUTH WATER WORKS
1 other system also serves parts of Portsmouth. 1 other system is listed for Portsmouth. See their figures
People Served
33,000
Health-based violations since 2020
0
PORTSMOUTH WATER WORKS. EPA SDWA violation data as of Q2 2026 (downloaded 2026-07-09).
Is Portsmouth Tap Water Safe to Drink?
We recommend using a certified water filter for additional protection, especially for vulnerable populations like children, pregnant women, and those with compromised immune systems. Portsmouth's water has 2 contaminants above EPA health-based guidelines (MCLGs), while it meets federal legal limits.
PORTSMOUTH WATER WORKS, Portsmouth's water system, serves 33,000 people. 1 other system also serves parts of Portsmouth. 1 other system is listed for Portsmouth. Each system's results are listed under its own name, never added to PORTSMOUTH WATER WORKS's. Water quality testing is conducted regularly and reported to the EPA.
Boil water advisories are issued by water systems and state agencies, and they change from day to day. Boil water advisories in New Hampshire
Portsmouth Water Service Areas
What these numbers actually mean for Portsmouth, NH
We read Portsmouth, NH’s published record and send you a short report — which findings warrant a decision, which to ignore, and what to do about it. Including when the answer is nothing.
- 2 contaminants above EPA MCLGs
- 23 results on file
- 23 PFAS compounds on record
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Recommended Water Filters for Portsmouth
Based on Portsmouth's water quality data, these NSF-certified filters are recommended to remove contaminants above EPA MCLGs.
Culligan
ZeroWater
NSF Certified:
Flow Rate
1.9 gpm
Daily Production
1 gpd
Highlights:
- Compact design
- Easy to set up
- Affordable
- NSF-42, NSF-53, NSF-401 certified
Removes 19 contaminants:
+14 more
Strontium, Molybdenum, Fluoride, Uranium, Lead, Total PFAS, Chlorine, 25, Phosphorus, Bicarbonate, Calcium, Carbonate, Magnesium, Sodium
Santevia
Bath Filter
NSF Certified:
Flow Rate
0.36 gpm
Highlights:
- Organic cotton design reduces plastic used in construction
- Affordable upfront & ongoing cost
- The only bath filter that removed 100% chlorine with “normal” faster faucet flow
Removes 1 contaminants:
Waterdrop
A1
NSF Certified:
Flow Rate
1 gpm
Highlights:
- Performance certified
- Lower price than Philips
- Hot water dispensing
- Compact design
Removes 5 contaminants:
Whirlpool Corporation
W11256135
NSF Certified:
Capacity
1001 gal
Filter Life
3 mo
Flow Rate
0.7 gpm
Removes 19 contaminants:
+14 more
Benzene, Carbofuran, Chlorine (Free), Chlorine (Total), Chlorine Dioxide, Chlorobenzene, Cryptosporidium, Ethylbenzene, Lead, Mercury, Metolachlor, Tetrachloroethylene, Toxaphene, Turbidity
Test Your Water Quality
Professional laboratory testing provides accurate, detailed analysis of your drinking water.
SimpleLab
Advanced Home Water Test
$269
Comprehensive water analysis testing over 200 contaminants including bacteria, heavy metals, and chemical compounds.
Tap Score
PFAS Forever Chemicals Test
$339.95
Specialized test for PFOA, PFOS, and 24 other forever chemicals. Essential for areas near military bases, airports, or industrial sites.
Tap Score
Advanced Microplastics Test
$829
Cutting-edge testing for microplastics particles in drinking water using advanced laboratory techniques.
What Portsmouth's water readings can explain
We publish a city-level hardness figure for Portsmouth, resolved from its water systems where they report one and estimated from county sampling where they do not. Each page starts with the hot-tap and cold-tap check, then shows what your own water system reported.
On a private well near Portsmouth? Public-water results do not apply to private wells. See Rockingham County well water testing and USGS risk data — modeled arsenic, nitrate, and the tests to run.
Water softener cost and installation in Portsmouth
Portsmouth's tap water has an estimated 7.2 grains per gallon (123.0 mg/L, county sampling in Rockingham County) — hard on the USGS scale, the range where scale on fixtures and appliances is the usual complaint.
Water softener cost for an estimated 7.2 gpg water in Portsmouth — equipment and local installation labour for your ZIP code, with the sizing arithmetic shown in full. For the national picture first, read what a water softener costs — equipment, installation labour and ten-year ownership, each separated out. For New Hampshire as a whole, read water softener cost in New Hampshire — priced against the plumber wage published for the state.
Frequently Asked Questions About Portsmouth Tap Water
Portsmouth's water has 2 contaminants above EPA MCLGs. While the water meets federal legal limits, we recommend using a certified water filter for additional protection, especially for vulnerable populations like children, pregnant women, and those with compromised immune systems.
Spotted something off on this page?
Residents keep our data honest.
This form corrects our data; it does not reach PORTSMOUTH WATER WORKS. For a problem with your water now (discolored water, no water, low pressure, a leak), contact PORTSMOUTH WATER WORKS directly.
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